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101.
102.
Elia Bari Ilaria Roato Giuseppe Perale Filippo Rossi Tullio Genova Federico Mussano Riccardo Ferracini Marzio Sorlini Maria Luisa Torre Sara Perteghella 《International journal of molecular sciences》2021,22(8)
SmartBone® (SB) is a biohybrid bone substitute advantageously proposed as a class III medical device for bone regeneration in reconstructive surgeries (oral, maxillofacial, orthopedic, and oncology). In the present study, a new strategy to improve SB osteoinductivity was developed. SB scaffolds were loaded with lyosecretome, a freeze-dried formulation of mesenchymal stem cell (MSC)-secretome, containing proteins and extracellular vesicles (EVs). Lyosecretome-loaded SB scaffolds (SBlyo) were prepared using an absorption method. A burst release of proteins and EVs (38% and 50% after 30 min, respectively) was observed, and then proteins were released more slowly with respect to EVs, most likely because they more strongly adsorbed onto the SB surface. In vitro tests were conducted using adipose tissue-derived stromal vascular fraction (SVF) plated on SB or SBlyo. After 14 days, significant cell proliferation improvement was observed on SBlyo with respect to SB, where cells filled the cavities between the native trabeculae. On SB, on the other hand, the process was still present, but tissue formation was less organized at 60 days. On both scaffolds, cells differentiated into osteoblasts and were able to mineralize after 60 days. Nonetheless, SBlyo showed a higher expression of osteoblast markers and a higher quantity of newly formed trabeculae than SB alone. The quantification analysis of the newly formed mineralized tissue and the immunohistochemical studies demonstrated that SBlyo induces bone formation more effectively. This osteoinductive effect is likely due to the osteogenic factors present in the lyosecretome, such as fibronectin, alpha-2-macroglobulin, apolipoprotein A, and TGF-β. 相似文献
103.
Giuseppe Della Penna Daniele Magazzeni Sergio Orefice 《Knowledge and Information Systems》2012,30(3):667-692
The Spatial Relation Query (SRQ) tool is a graphical software environment, supported by a SQL-like language, which enables
users to perform information extraction driven by the visual appearance and the spatial arrangement of the information. The
tool has been initially customised to work on specific application domains, like web pages and geospatial data. In this paper,
we present the theoretical formalisation of the visual information extraction (VIE) task and accordingly the redesign of the
SRQ tool, which is now a full-featured, general-purpose information extraction system. Moreover, we show a new application
of the VIE framework to the analysis and visual information extraction from PDF files. 相似文献
104.
Daniela dell'Oro Francesco Casamassima Giuseppe Gesualdo Marco Iammarino Paolo Mambelli Valeria Nardelli 《International Journal of Food Science & Technology》2014,49(5):1391-1400
The aim of this study was to develop and validate an efficient analytical method based on gas chromatography/tandem mass spectrometry (GC/MS/MS) for detection and quantification of six pyrethroids residues (Phenothrin, Permethrin, Cyfluthrin, Cypermethrin, Deltamethrin and Fenvalerate) in chicken eggs. The method was based on a preliminary liquid–liquid extraction of albumen‐free yolk samples, followed by a clean‐up by solid‐phase extraction. GC/MS/MS analyses were carried out in the selected reaction monitoring mode. Validation parameters such as specificity, detection capability, decision limit, precision, recovery, stability and ruggedness were determined, resulting in compliance with Decision 2002/657/EC. No complicated apparatus are required; moreover, low volumes of organic solvents and a nonintensive manual labour are required. These low costs and simple procedure, based on rapid and safe operations, may represent a useful tool in the routine analysis of pyrethroids pesticides, in the place of the currently used conventional techniques. 相似文献
105.
Renato Colle Giuseppe Grosso Alberto Ronzani Massimo Gazzano Vincenzo Palermo 《Carbon》2012,50(3):1332-1337
We describe the self-assembly of soluble, chemically modified fullerene [6,6]-phenyl C61 butyric acid methyl ester (PCBM) into a new crystalline phase where the C60 moieties are arranged in parallel layers. Minimum C60 center-to-center distance is 10 Å within the layers, and up to 15 Å perpendicular to the layers. Highly anisotropic, mesoscopic hexagonal crystals of this material, with a lateral size of many microns and a thickness below 1 μm, are obtained from chloroform solution by solvent vapor annealing, and characterized by optical microscopy and X-ray diffraction. The crystalline structure is deduced combining experimental data with molecular modeling and ab initio calculations. The large difference in C60–C60 spacing indicates a high anisotropy in electrical and charge transport properties of this new phase. 相似文献
106.
107.
108.
Giuseppe Ritella Kai Hakkarainen 《International Journal of Computer-Supported Collaborative Learning》2012,7(2):239-258
The purpose of the present paper is to examine the socio-cultural foundations of technology-mediated collaborative learning. Toward that end, we discuss the role of artifacts in knowledge-creating inquiry, relying on the theoretical ideas of Carl Bereiter, Merlin Donald, Pierre Rabardel, Keith Sawyer and L. S. Vygotsky. We argue that epistemic mediation triggers expanded inquiry and plays a crucial role in knowledge creation; such mediation involves using CSCL technologies to create epistemic artifacts for crystallizing cognitive processes, re-mediating subsequent activity, and building an evolving body of knowledge. Productive integration of CSCL technologies as instruments of learning and instruction is a developmental process: it requires iterative efforts across extended periods of time. Going through such a process of instrumental genesis requires transforming a cognitive-cultural operating system of activity, thus ??reformatting?? the brain and the mind. Because of the required profound personal and social transformations, one sees that innovative knowledge-building practices emerge, socially, through extended expansive-learning cycles. 相似文献
109.
Filippo Rossi Xanthippi Chatzistavrou Giuseppe Perale Aldo R. Boccaccini 《应用聚合物科学杂志》2012,123(1):398-408
Hydrogels studied in this investigation, synthesized starting from agarose and Carbomer 974P, were chosen for their potential use in tissue engineering. The strong ability of hydrogels to mimic living tissues should be complemented with optimized degradation time profiles: a critical property for biomaterials but essential for the integration with target tissue. In this study, chosen hydrogels were characterized both from a rheological and a structural point of view before studying the chemistry of their degradation, which was performed by several analysis: infrared bond response [Fourier transform infrared (FT‐IR)], calorimetry [differential scanning Calorimetry (DSC)], and % mass loss. Degradation behaviors of Agar‐Carbomer hydrogels with different degrees of crosslinkers were evaluated monitoring peak shifts and thermal property changes. It was found that the amount of crosslinks heavily affect the time and the magnitude related to the process. The results indicate that the degradation rates of Agar‐Carbomer hydrogels can be controlled and tuned to adapt the hydrogel degradation kinetics for different cell housing and drug delivery applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
110.
A. C. H. Barreto F. J. N. Maia V. R. Santiago V. G. P. Ribeiro J. C. Denardin Giuseppe Mele L. Carbone Diego Lomonaco S. E. Mazzetto P. B. A. Fechine 《Microfluidics and nanofluidics》2012,12(5):677-686
In this work, we present the synthesis and characterization of a new surfactant molecule obtained from a byproduct of the
cashew nut processing (diphosphorylated cardol, DPC). It is herein used to overcoat magnetic nanoparticles showing spinel
structures in order to create new ferrofluids. The nanoparticle structure and magnetic properties have been deeply investigated.
DPC-functionalized Fe3O4 and NiFe2O4 samples exhibit higher magnetic saturation than DPC–CoFe2O4. These new ferrofluids reveal appealing as possible nanoparticle stabilizing molecules, magnetic resonance imaging agents,
storage systems or in any material science field that requires the employment of biocompatible magnetic stable fluids. 相似文献